4018 not accepting LLDP-MED assigned voice VLAN

[sweatyhairybollocks]

We are currently assigning Voice VLAN via the AVA method, but are looking to migrate this over to the LLDP-MED mechanism. Our switches (Juniper EX series) are sending the voice VLAN in LLDP, but the phone handsets are ignoring it and sending DHCP requests in the native VLAN. What do we need to enable on the phones to get them to recognise the LLDP advertisements and send out 802.1Q-tagged DHCP requests in the voice VLAN?

[sir_hiss]

Which Firmware is installed on the 4018 and is "VLAN = YES" at "LLDP" configured (default)?